儿童上尿路结石腔内手术治疗有效性和安全性预测模型的构建及其预测效能

Establishment and predictive efficiency of model for the effect and safety of endoscopic lithotripsy on pediatric upper urinary tract calculi

目的建立能够有效预测儿童上尿路结石腔内手术治疗后有效性及安全性的预测模型,并通过内部验证评估其诊断效能。方法回顾性分析2014年6月至2019年4月首都医科大学附属北京友谊医院348例泌尿系结石患儿的临床资料。男250例,女98例。中位年龄3.0(1.4~7.0)岁。中位体质指数17.1(15.0,19.5)kg/m^2。术前发热40例;尿细菌培养阳性170例。结石CT值665<(461,912)HU。结石负荷1.77(0.64,3.14)cm^2;结石复杂度分级1级183例,2级38例,3级33例,4级124例。348例患儿共行腔内手术375次,其中可视经皮肾镜取石术(Micro-perc)27次,超微经皮肾镜取石术(Ulta-Mini-PCNL)26次,微经皮肾镜取石术(Mini-PCNL)8次,输尿管硬镜碎石术(RURS)10次,输尿管软镜碎石术(FURS)288次,PCNL+FURS 16次;手术时间30(20,40)min;术中灌注量500(200.1000)ml。采用单因素和多因素logistice回归分析评估、筛选结石清除率(SFR)和并发症发生率(CR)的预测因素。利用分析得到的预测因素构建SFR和CR的预测模型。采用曲线下面积(AUC)评估模型的区分度;校准曲线评估预测概率与实际风险的-致性;决策曲线评估模型应用的临床获益情况。结果本研究手术的整体SFR为88.0%(330/375);CR为23.2%(87/375),其中术后血尿(I级)45例,术后发热(I级)40例,石街形成(皿级)2例。综合单因素和多因素logistic分析结果,结石负荷、手术时间、术中灌注量、结石位置和手术方式是儿童结石腔内手术后SFR和CR的共同预测因素。除以上因素外,体质指数同样为术后CR的预测因素。基于以上预测因素构建SFR和CR预测模型,其AUC分别为0.81和0.73;校准曲线显示模型的预测概率与实际值具有较好的一致性;决策曲线显示,SFR预测模型阈值>20%时具有明显的临床获益;CR预测模型阈值>10%时具有明显的临床获益。结论内部验证证实基于结石负荷、手术时间、术中灌注量、结石位置、手术方式及体质指数等因索构建的预测模型对于儿童结石腔内手术治疗后的有效性及安全性具有较好的预测效能。患儿的体质指数是腔内手术治疗安全性的重要影响因素。

Objective To establish a predictive model that can predict the effectiveness and safety of endoscopic surgery for pediatric upper urinary tract calculi,and evaluate its diagnostic efficacy through internal validation.Methods The data was selected from the prospective database of pediatric upper tract calculi constructed by Beijing Friendship Hospital Affiliated to Capital Medical University from June 2014 to April 2019.A total of 348 children were recruited in this investigation including 250 boys and 98 girls,with a median age of 3.0 years(Interquartile Range 1.4,7.0 years).Totally 375 endoscopic surgeries were performed,with an overall stone free rate(SF'R)of 88.0%(330/375)and complication rate(C R)of 23.2%(87/375).This research used univariate and multivariate logistic regression analysis to evaluate and screen the predictors of SFR and CR.The nomogram of SFR and CR was established by using the selected predictive factors.The differentiation degree of the model was evaluated by the area under the curve(AUC),the consistency between the prediction probability and the actual risk was evaluated by the calibration curve,and the clinical benefits of the model application were assessed by the decision curve.Results The results of multivariate analysis demonstrated that stone burden,operation duration,intraoperative perfusion,stone location and operative options were the postoperative predictors of SFR and CR for children.Besides,BMI was also a predictor of postoperative CR.The AUC of the model(model 1:SFR;model 2:C R)based on the above predictive factors was 0.81 and 0.73,respectively.The predictive probability of the calibration curve showed that the model had a good consistency with the actual value.The decision curve showed that the application of model 1 to predict SFR had significant clinical benefits when the threshold value was greater than 20%,and the application of model 2 to predict the postoperative CR had a significant clinical benefit when the threshold was greater than 10%.Conclusions Nomogram based on stone burden,operation time,intraoperative perfusion,stone location and operative options was validated internally with preferable predictive power on the effectiveness and safety of pediatric endoscopic surgery.This model can be used to predict the clinical effects of pediatric endoscopic lithotripsy.BMI was also an important factor for the safety of pediatric endoscopic procedures.